The story focuses on a group of passengers aboard The Chief running from Los Angeles to Chicago, where they plan to catch the onward 20th Century to the East Coast. They include the powerful Hollywood film mogul Vivien Spender as well as his leading star Kitten Agnew, a cynical bandleader, an alcoholic newspaperman as well as Gloria, the innocent, former librarian who Spender has chosen to replace Kitten. However, Kitten
refuses to be abandoned the way Spender has dumped countless earlier protegees and has incriminating information against him.
She becomes increasingly fearful of Spender, who behind his urbane facade, is ruthless enough to kill her to get rid of her. As the train passes through Kansas, Kitten is discovered dead in her compartment. The other passengers decide to stand up to Spender and expose him as the murderer of both Kitten and his first wife. Rather than let this happen, Spender's ever loyal secretary chooses to take matters into her own hands.
